In the production of foams, including polyurethane, agents such as hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs) etc are employed as foaming agents. These materials also find use as cleaning agents or solvents and refrigerants. Various chemicals are included in foam or polyol premixes. These chemicals can include polyols, catalysts, surfactants, fire retardants, etc. Trans-1,2-dichloroethylene (TDCE) is a known agent employed in foam production and in cleaning agent, solvent and refrigerant applications.
Handling of Trans-1,2-dichloroethylene or TDCE is problematic because of its relatively low flash point of −10° C. Flash point as used herein relates to flash point as measured using a Setaflash “series 7” flash point tester. Current United States Department of Transportation regulations designate liquids having a flash point less of than 60° C. as flammable for transportation purposes. Thus, transportation of TDCE such as for use in foam production is problematic.
Prior methods to provide “non-flammable” TDCE have focused on mixing it with a large quantity non-flammable compound having a volatility similar to TDCE. Furthermore, prior methods relied upon forming azeotrope blends of TDCE and other components to suppress (raise) the flash point. For example Novec™ engineered fluid HFE-71DE available from Minnesota Mining and Manufacturing Co. comprises an azeotropic blend of TDCE and 1-(Methoxy)nonafluorobutane (C4 F9 OCH3). The blend consists of 50% by weight of 1-(Methoxy)nonafluorobutane. This blend is non-flammable and has no flash point. Such prior methods resulted in adding an additional volatile compound or compounds to TDCE which compounds can become incorporated into the foam produced with the mixture. Similarly, a product (Vertrel® MCA) available from DuPont is an azeotropic blend consisting of about 62% by weight of 1,1,1,2,2,3,4,5,5,5-decafluoropentance (HFC-4310mee) and about 38% by weight of TDCE.
U.S. Pat. No. 5,759,986 discloses an azeotropic or azeotropic like composition of 40 to 70% by weight 1,1,1,2,2,3,4,5,5,5-decafluoropentane (HFC-4310mee), 15-50% TDCE, 1-25% cyclopentane and 1-10% methanol or 35-75% by weight HFC-4310mee, 10-50% TDCE and 5-25% cyclopentane. No specific mention is made of flash point or boiling point for the described azeotropic or azeotropic like composition. The use of significant proportions of volatile compounds such as HFC-4310mee, adds to the global warming potential (GWP) of the mixture. These results are undesirable.
U.S. Pat. No. 5,196,137 discloses an azeotropic mixture of 1,1,1,2,3,4,4,5,5,5-decafluoropentane (HFC-4310mee) and trans-1,2-dichloroethylene, cis-1,1-diehloroethylene or 1,1-dichloroethane. The disclosed azeotropic mixture of HFC-4310mee and TDCE consists essentially of 58 to 68 weight percent HFC-4310mee and 32 to 42 weight percent TDCE. The use of a significant proportion of volatile compounds such as HFC-4310mee, adds to the global warming potential (GWP) of the mixture. These results are undesirable.
U.S. Pat. No. 5,827,812 discloses azeotrope or azeotrope like compositions including a composition consisting essentially of about 25 to 83 weight percent TDCE and about 75 to 17 weight percent perfluorobutyl methyl ether. The use of a significant proportion of volatile compounds such as perfluorobutyl methyl ethers, adds to the global warming potential (GWP) of the mixture. These results are undesirable.
U.S. Pat. No. 6,793,840 discloses a binary azeotropic composition of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and TDCE, which consists of 30.7 mole % of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and 69.3 mole % of TDCE. This composition is equivalent to 52.9% by weight of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene. Again, a higher proportion of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene in the blend is undesirable.